ref: dc736a6ac0d6abe15da0139a00e205e84f82deec
dir: /src/base/ftglyph.c/
/***************************************************************************/ /* */ /* ftglyph.c */ /* */ /* FreeType convenience functions to handle glyphs (body). */ /* */ /* Copyright 1996-2001, 2002, 2003, 2004 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ /* modified, and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ /*************************************************************************/ /* */ /* This file contains the definition of several convenience functions */ /* that can be used by client applications to easily retrieve glyph */ /* bitmaps and outlines from a given face. */ /* */ /* These functions should be optional if you are writing a font server */ /* or text layout engine on top of FreeType. However, they are pretty */ /* handy for many other simple uses of the library. */ /* */ /*************************************************************************/ #include <ft2build.h> #include FT_GLYPH_H #include FT_OUTLINE_H #include FT_INTERNAL_OBJECTS_H /*************************************************************************/ /* */ /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ /* messages during execution. */ /* */ #undef FT_COMPONENT #define FT_COMPONENT trace_glyph /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** Convenience functions ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ /* documentation is in ftglyph.h */ FT_EXPORT_DEF( void ) FT_Matrix_Multiply( const FT_Matrix* a, FT_Matrix *b ) { FT_Fixed xx, xy, yx, yy; if ( !a || !b ) return; xx = FT_MulFix( a->xx, b->xx ) + FT_MulFix( a->xy, b->yx ); xy = FT_MulFix( a->xx, b->xy ) + FT_MulFix( a->xy, b->yy ); yx = FT_MulFix( a->yx, b->xx ) + FT_MulFix( a->yy, b->yx ); yy = FT_MulFix( a->yx, b->xy ) + FT_MulFix( a->yy, b->yy ); b->xx = xx; b->xy = xy; b->yx = yx; b->yy = yy; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( FT_Error ) FT_Matrix_Invert( FT_Matrix* matrix ) { FT_Pos delta, xx, yy; if ( !matrix ) return FT_Err_Invalid_Argument; /* compute discriminant */ delta = FT_MulFix( matrix->xx, matrix->yy ) - FT_MulFix( matrix->xy, matrix->yx ); if ( !delta ) return FT_Err_Invalid_Argument; /* matrix can't be inverted */ matrix->xy = - FT_DivFix( matrix->xy, delta ); matrix->yx = - FT_DivFix( matrix->yx, delta ); xx = matrix->xx; yy = matrix->yy; matrix->xx = FT_DivFix( yy, delta ); matrix->yy = FT_DivFix( xx, delta ); return FT_Err_Ok; } /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** FT_BitmapGlyph support ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ static FT_Error ft_bitmap_copy( FT_Memory memory, FT_Bitmap* source, FT_Bitmap* target ) { FT_Error error; FT_Int pitch = source->pitch; FT_ULong size; *target = *source; if ( pitch < 0 ) pitch = -pitch; size = (FT_ULong)( pitch * source->rows ); if ( !FT_ALLOC( target->buffer, size ) ) FT_MEM_COPY( target->buffer, source->buffer, size ); return error; } FT_CALLBACK_DEF( FT_Error ) ft_bitmap_glyph_init( FT_Glyph bitmap_glyph, FT_GlyphSlot slot ) { FT_BitmapGlyph glyph = (FT_BitmapGlyph)bitmap_glyph; FT_Error error = FT_Err_Ok; FT_Library library = FT_GLYPH( glyph )->library; FT_Memory memory = library->memory; if ( slot->format != FT_GLYPH_FORMAT_BITMAP ) { error = FT_Err_Invalid_Glyph_Format; goto Exit; } /* grab the bitmap in the slot - do lazy copying whenever possible */ glyph->bitmap = slot->bitmap; glyph->left = slot->bitmap_left; glyph->top = slot->bitmap_top; if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP ) slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP; else { /* copy the bitmap into a new buffer */ error = ft_bitmap_copy( memory, &slot->bitmap, &glyph->bitmap ); } Exit: return error; } FT_CALLBACK_DEF( FT_Error ) ft_bitmap_glyph_copy( FT_Glyph bitmap_source, FT_Glyph bitmap_target ) { FT_BitmapGlyph source = (FT_BitmapGlyph)bitmap_source; FT_BitmapGlyph target = (FT_BitmapGlyph)bitmap_target; FT_Memory memory = bitmap_source->library->memory; target->left = source->left; target->top = source->top; return ft_bitmap_copy( memory, &source->bitmap, &target->bitmap ); } FT_CALLBACK_DEF( void ) ft_bitmap_glyph_done( FT_Glyph bitmap_glyph ) { FT_BitmapGlyph glyph = (FT_BitmapGlyph)bitmap_glyph; FT_Memory memory = FT_GLYPH( glyph )->library->memory; FT_FREE( glyph->bitmap.buffer ); } FT_CALLBACK_DEF( void ) ft_bitmap_glyph_bbox( FT_Glyph bitmap_glyph, FT_BBox* cbox ) { FT_BitmapGlyph glyph = (FT_BitmapGlyph)bitmap_glyph; cbox->xMin = glyph->left << 6; cbox->xMax = cbox->xMin + ( glyph->bitmap.width << 6 ); cbox->yMax = glyph->top << 6; cbox->yMin = cbox->yMax - ( glyph->bitmap.rows << 6 ); } FT_CALLBACK_TABLE_DEF const FT_Glyph_Class ft_bitmap_glyph_class = { sizeof ( FT_BitmapGlyphRec ), FT_GLYPH_FORMAT_BITMAP, ft_bitmap_glyph_init, ft_bitmap_glyph_done, ft_bitmap_glyph_copy, 0, /* FT_Glyph_TransformFunc */ ft_bitmap_glyph_bbox, 0 /* FT_Glyph_PrepareFunc */ }; /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** FT_OutlineGlyph support ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ FT_CALLBACK_DEF( FT_Error ) ft_outline_glyph_init( FT_Glyph outline_glyph, FT_GlyphSlot slot ) { FT_OutlineGlyph glyph = (FT_OutlineGlyph)outline_glyph; FT_Error error = FT_Err_Ok; FT_Library library = FT_GLYPH( glyph )->library; FT_Outline* source = &slot->outline; FT_Outline* target = &glyph->outline; /* check format in glyph slot */ if ( slot->format != FT_GLYPH_FORMAT_OUTLINE ) { error = FT_Err_Invalid_Glyph_Format; goto Exit; } /* allocate new outline */ error = FT_Outline_New( library, source->n_points, source->n_contours, &glyph->outline ); if ( error ) goto Exit; /* copy it */ FT_ARRAY_COPY( target->points, source->points, source->n_points ); FT_ARRAY_COPY( target->tags, source->tags, source->n_points ); FT_ARRAY_COPY( target->contours, source->contours, source->n_contours ); /* copy all flags, except the `FT_OUTLINE_OWNER' one */ target->flags = source->flags | FT_OUTLINE_OWNER; Exit: return error; } FT_CALLBACK_DEF( void ) ft_outline_glyph_done( FT_Glyph outline_glyph ) { FT_OutlineGlyph glyph = (FT_OutlineGlyph)outline_glyph; FT_Outline_Done( FT_GLYPH( glyph )->library, &glyph->outline ); } FT_CALLBACK_DEF( FT_Error ) ft_outline_glyph_copy( FT_Glyph outline_source, FT_Glyph outline_target ) { FT_OutlineGlyph source = (FT_OutlineGlyph)outline_source; FT_OutlineGlyph target = (FT_OutlineGlyph)outline_target; FT_Error error; FT_Library library = FT_GLYPH( source )->library; error = FT_Outline_New( library, source->outline.n_points, source->outline.n_contours, &target->outline ); if ( !error ) FT_Outline_Copy( &source->outline, &target->outline ); return error; } FT_CALLBACK_DEF( void ) ft_outline_glyph_transform( FT_Glyph outline_glyph, FT_Matrix* matrix, FT_Vector* delta ) { FT_OutlineGlyph glyph = (FT_OutlineGlyph)outline_glyph; if ( matrix ) FT_Outline_Transform( &glyph->outline, matrix ); if ( delta ) FT_Outline_Translate( &glyph->outline, delta->x, delta->y ); } FT_CALLBACK_DEF( void ) ft_outline_glyph_bbox( FT_Glyph outline_glyph, FT_BBox* bbox ) { FT_OutlineGlyph glyph = (FT_OutlineGlyph)outline_glyph; FT_Outline_Get_CBox( &glyph->outline, bbox ); } FT_CALLBACK_DEF( FT_Error ) ft_outline_glyph_prepare( FT_Glyph outline_glyph, FT_GlyphSlot slot ) { FT_OutlineGlyph glyph = (FT_OutlineGlyph)outline_glyph; slot->format = FT_GLYPH_FORMAT_OUTLINE; slot->outline = glyph->outline; slot->outline.flags &= ~FT_OUTLINE_OWNER; return FT_Err_Ok; } FT_CALLBACK_TABLE_DEF const FT_Glyph_Class ft_outline_glyph_class = { sizeof ( FT_OutlineGlyphRec ), FT_GLYPH_FORMAT_OUTLINE, ft_outline_glyph_init, ft_outline_glyph_done, ft_outline_glyph_copy, ft_outline_glyph_transform, ft_outline_glyph_bbox, ft_outline_glyph_prepare }; /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** FT_Glyph class and API ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ static FT_Error ft_new_glyph( FT_Library library, const FT_Glyph_Class* clazz, FT_Glyph* aglyph ) { FT_Memory memory = library->memory; FT_Error error; FT_Glyph glyph; *aglyph = 0; if ( !FT_ALLOC( glyph, clazz->glyph_size ) ) { glyph->library = library; glyph->clazz = clazz; glyph->format = clazz->glyph_format; *aglyph = glyph; } return error; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( FT_Error ) FT_Glyph_Copy( FT_Glyph source, FT_Glyph *target ) { FT_Glyph copy; FT_Error error; const FT_Glyph_Class* clazz; /* check arguments */ if ( !target || !source || !source->clazz ) { error = FT_Err_Invalid_Argument; goto Exit; } *target = 0; clazz = source->clazz; error = ft_new_glyph( source->library, clazz, © ); if ( error ) goto Exit; copy->advance = source->advance; copy->format = source->format; if ( clazz->glyph_copy ) error = clazz->glyph_copy( source, copy ); if ( error ) FT_Done_Glyph( copy ); else *target = copy; Exit: return error; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( FT_Error ) FT_Get_Glyph( FT_GlyphSlot slot, FT_Glyph *aglyph ) { FT_Library library; FT_Error error; FT_Glyph glyph; const FT_Glyph_Class* clazz = 0; if ( !slot ) return FT_Err_Invalid_Slot_Handle; library = slot->library; if ( !aglyph ) return FT_Err_Invalid_Argument; /* if it is a bitmap, that's easy :-) */ if ( slot->format == FT_GLYPH_FORMAT_BITMAP ) clazz = &ft_bitmap_glyph_class; /* it it is an outline too */ else if ( slot->format == FT_GLYPH_FORMAT_OUTLINE ) clazz = &ft_outline_glyph_class; else { /* try to find a renderer that supports the glyph image format */ FT_Renderer render = FT_Lookup_Renderer( library, slot->format, 0 ); if ( render ) clazz = &render->glyph_class; } if ( !clazz ) { error = FT_Err_Invalid_Glyph_Format; goto Exit; } /* create FT_Glyph object */ error = ft_new_glyph( library, clazz, &glyph ); if ( error ) goto Exit; /* copy advance while converting it to 16.16 format */ glyph->advance.x = slot->advance.x << 10; glyph->advance.y = slot->advance.y << 10; /* now import the image from the glyph slot */ error = clazz->glyph_init( glyph, slot ); /* if an error occurred, destroy the glyph */ if ( error ) FT_Done_Glyph( glyph ); else *aglyph = glyph; Exit: return error; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( FT_Error ) FT_Glyph_Transform( FT_Glyph glyph, FT_Matrix* matrix, FT_Vector* delta ) { const FT_Glyph_Class* clazz; FT_Error error = FT_Err_Ok; if ( !glyph || !glyph->clazz ) error = FT_Err_Invalid_Argument; else { clazz = glyph->clazz; if ( clazz->glyph_transform ) { /* transform glyph image */ clazz->glyph_transform( glyph, matrix, delta ); /* transform advance vector */ if ( matrix ) FT_Vector_Transform( &glyph->advance, matrix ); } else error = FT_Err_Invalid_Glyph_Format; } return error; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( void ) FT_Glyph_Get_CBox( FT_Glyph glyph, FT_UInt bbox_mode, FT_BBox *acbox ) { const FT_Glyph_Class* clazz; if ( !acbox ) return; acbox->xMin = acbox->yMin = acbox->xMax = acbox->yMax = 0; if ( !glyph || !glyph->clazz ) return; else { clazz = glyph->clazz; if ( !clazz->glyph_bbox ) return; else { /* retrieve bbox in 26.6 coordinates */ clazz->glyph_bbox( glyph, acbox ); /* perform grid fitting if needed */ if ( bbox_mode == FT_GLYPH_BBOX_GRIDFIT || bbox_mode == FT_GLYPH_BBOX_PIXELS ) { acbox->xMin = FT_PIX_FLOOR( acbox->xMin ); acbox->yMin = FT_PIX_FLOOR( acbox->yMin ); acbox->xMax = FT_PIX_CEIL( acbox->xMax ); acbox->yMax = FT_PIX_CEIL( acbox->yMax ); } /* convert to integer pixels if needed */ if ( bbox_mode == FT_GLYPH_BBOX_TRUNCATE || bbox_mode == FT_GLYPH_BBOX_PIXELS ) { acbox->xMin >>= 6; acbox->yMin >>= 6; acbox->xMax >>= 6; acbox->yMax >>= 6; } } } return; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( FT_Error ) FT_Glyph_To_Bitmap( FT_Glyph* the_glyph, FT_Render_Mode render_mode, FT_Vector* origin, FT_Bool destroy ) { FT_GlyphSlotRec dummy; FT_GlyphSlot_InternalRec dummy_internal; FT_Error error = FT_Err_Ok; FT_Glyph glyph; FT_BitmapGlyph bitmap = NULL; const FT_Glyph_Class* clazz; /* check argument */ if ( !the_glyph ) goto Bad; /* we render the glyph into a glyph bitmap using a `dummy' glyph slot */ /* then calling FT_Render_Glyph_Internal() */ glyph = *the_glyph; if ( !glyph ) goto Bad; clazz = glyph->clazz; /* when called with a bitmap glyph, do nothing and return successfully */ if ( clazz == &ft_bitmap_glyph_class ) goto Exit; if ( !clazz || !clazz->glyph_prepare ) goto Bad; FT_MEM_ZERO( &dummy, sizeof ( dummy ) ); FT_MEM_ZERO( &dummy_internal, sizeof ( dummy_internal ) ); dummy.internal = &dummy_internal; dummy.library = glyph->library; dummy.format = clazz->glyph_format; /* create result bitmap glyph */ error = ft_new_glyph( glyph->library, &ft_bitmap_glyph_class, (FT_Glyph*)&bitmap ); if ( error ) goto Exit; #if 1 /* if `origin' is set, translate the glyph image */ if ( origin ) FT_Glyph_Transform( glyph, 0, origin ); #else FT_UNUSED( origin ); #endif /* prepare dummy slot for rendering */ error = clazz->glyph_prepare( glyph, &dummy ); if ( !error ) error = FT_Render_Glyph_Internal( glyph->library, &dummy, render_mode ); #if 1 if ( !destroy && origin ) { FT_Vector v; v.x = -origin->x; v.y = -origin->y; FT_Glyph_Transform( glyph, 0, &v ); } #endif if ( error ) goto Exit; /* in case of success, copy the bitmap to the glyph bitmap */ error = ft_bitmap_glyph_init( (FT_Glyph)bitmap, &dummy ); if ( error ) goto Exit; /* copy advance */ bitmap->root.advance = glyph->advance; if ( destroy ) FT_Done_Glyph( glyph ); *the_glyph = FT_GLYPH( bitmap ); Exit: if ( error && bitmap ) FT_Done_Glyph( FT_GLYPH( bitmap ) ); return error; Bad: error = FT_Err_Invalid_Argument; goto Exit; } /* documentation is in ftglyph.h */ FT_EXPORT_DEF( void ) FT_Done_Glyph( FT_Glyph glyph ) { if ( glyph ) { FT_Memory memory = glyph->library->memory; const FT_Glyph_Class* clazz = glyph->clazz; if ( clazz->glyph_done ) clazz->glyph_done( glyph ); FT_FREE( glyph ); } } /* END */